Printed circuit board



nouw m, w. mgm z www M .w wim@ rm R www5 n f ,K ya@ /M W5 fam #m5 June9, 1964 H. SCHWAB ETAL PRINTED CIRCUIT BOARD FILE Orlglnal Flled Deo 271960 United States Patent O 25,595 PRINTED CIRCUIT BOARD FILE HelmutSchwab, Altadena, Stanley E. Beale, Bradbury, and Tage O. Anderson,Arcadia, Calif., assignors to Applied Development Corporation, MontereyPark,

Calif., a corporation of California Original No. 3,017,232, dated Jan.16, 1962, Ser. No.

78,730, Dec. 27, 1960. Application for reissue Aug.

15, 1963, Ser. No. 303,722

15 Claims. (Cl. 339-176) Matter enclosed in heavy brackets appears inthe original patent but forms no part of this reissue speeltication;matter printed in italics indicates the additions made by reissue.

This invention relates to apparatus for tiling printed circuit boards orcards and more particularly to modular hardware that may be readilysnapped together for assembling a circuit board receptacle and therebyallow circuit boards to be readily placed into and out of circuitrelationship therewith.

With the development of data processing installations, large, complexsystems have been a result. These data processing systems have oftenbeen constructed of a bewildering and often inconsistent array ofequipment. The design of these systems has evolved in terms of circuitmodules to simplify the manufacture, assembly, and maintenance thereof.A large number of the circuit modules have been used in the form ofpluggable printed circuit boards or cards whereby a faulty circuit ormodication in circuit design may be readily realized by withdrawing acircuit card and replacing it with a new one. The new card necessarilyhas the same physical dimensions as the one it replaces and generallyincludes an electrical connector mounted with each card. Therefore, thedesign of hardware to house the circuits, including the printed circuitcards, has been an important factor in the overall design of an eicient,economical data processing system. Consistent with modular constructiontechniques, the printed circuit cards have been stored and filed indrawers that allow ready access to any group of printed circuit cards.As contrasted with the earlier types of pluggable circuitry, this typeof an assembly did not include an electrical connector with each printedcircuit card but, instead, the connector was an integral part of thedrawer. This type of construction required that the printed circuitboard may be readily and easily inserted into the stationary electricalconnector. This necessarily implies the correct alignment between theelements for guiding the circuit board into correct electricalrelationship with its connector. These circuit drawers and theirassociated electrical connectors have been manufactured by means ofsheetrnetal techniques wherein each of the :components thereof areseparately manufactured and, therefore, must be accurately aligned uponassembly. The 'alignment problems are serious since a slightmisalignment prevents ready entry of a circuit board into its connectorand even more difficulty in their removal, sometimes requiring a largeamount of force to be used leading to breakage of the circuit carditself. These alignment problems lead to high manufacturing costs. Itis, therefore, advantageous to provide electronic hardware thateliminates the expense of sheetmetal assembly and particularly thealignment problems associated therewith and yet provide a simple,flexible, and economic arrangements for rigidly mounting circuit cards.

This invention provides improved hardware for filing printed circuitscards and which hardware is inexpensive, exible, extremely reliable, andcompatible with almost every data environment. The improved hardwarecomprises modular elements that may be snapped together for forming anassembly for receiving and storing a Re. 25,595 ,leissued June 9, 1964ICC printed circuit card. The modular elements have been standardized toallow quantity production and the resulting low cost, and Ilyetsuiciently flexible to be put together to any system configuration ormodification thereof.

The electronic modular hardware includes a pair of printed circuit boardguiding elements that are adapted to be mounted on holding elements andclamped thereto by a split-ring locking element. The guiding elementsare provided with socket portions adjacent their opposite ends to hug aholding element such as a rod when clamped thereto. On the opposite sidefrom the socket elements a guide slot or track is defined longitudinallythereof to slidably receive and hold a corresponding edge of a printedcircuit card. The guiding elements are further defined with outwardlyextending locking ears arranged transversely thereto to extend apredetermined distance along the holding element for coaction with alocking element. The locking elements are constructed in the form of aresilient plastic so that it may be slightly expanded to allow it toslip over the holding member and to receive and hug the locking earsarranged on opposite sides of a holding member to cause the guidingelement to be snap-locked thereto when the locking element tends toassume its normal shape. The modular assembly or receptacle is completedby securing a conventional electrical circuit card connector to the pairof aligned guiding elements by means of a preformed aperture thereonwhereby the socket for the electrical connector is always aligned withthe slots or tracks for the guiding elements. This arrangement allowsthe circuit card to be easily slipped into the electrical connector bymeans of the guide slots and to be rigidly and accurately retainedtherein.

These modular elements may be further mounted on the holding memberswith the locking ears of a separately aligned pair of guiding elementsarranged in a sideby-side alignment whereby a single locking elementwill function to snap-lock the locking ears of adjacent guiding elementsto the holding members and which locking elements may be defined invarious sizes to function as a spacer between successively stored cards.This arranement may then be utilized as a separate modular assembly orbe placed in a le drawer compatible with the other digital systemhardware.

These and other features of the present invention may be more fullyappreciated when considered in the light of the following specificationand drawings, in which:

FIG. 1 is an exploded view of the modular elements arranged aboutholding elements and embodying the invention;

FIG. 2 is a perspective View of a portion of a modular sub-assemblyemploying the modular elements of FIG. l and showing a circuit card in apartially ejected relationship in dotted outline; and

FIG. 3 is a perspective view of a typical file drawer for storing thesubassemblies of the type of FIG. 2 and including a swingable ling unit.

Referring now to the drawings, the structure for each of the modularelements allowing them to be snapped together to form a modular assemblyor receptacle for storing and filing printed circuit boards will bedescribed. Basically, the modular hardware comprises a guiding element10, a locking element 12, and an electrical connector 14 for use with aprinted circuit `card or board 16. These modular elements are clamped orsnapped to holding elements shown as the rods 18. In some applicationsVit may be found convenient to provide the printed circuit card 16 witha handle or card puller 20.

To simplify the illustration of the invention and the correspondingdescription, the printed circuit card 16 and its associated electricalcomponents are not illustrated except for the printed electricalconductors 16a adjacent the lower edge of the circuit board 16, as shownin FIG. 1. In this connection it should be understood :hat theelectrical connector 14 is a conventional, commercially availableconnector and, for the purposes of this invention, it merely need benoted that it includes a socket portion 14a to receive the lower edge ofthe record card 16 whereby the printed circuit portions 16a will bealigned with the respective electrical terminals for the connector 14.

The guiding elements itll comprise an elongate element :onstructed of aresilient plastic, such as nylon, and which may be formed by means of aninjection molding grocess. The guiding elements 1l! are formed withhold- .ng sockets adjacent their opposite ends, similar to the socket1)a defined to receive and hug a holding element Jr rod 18. The guidingelements are further defined avith locking elements or ears similar tothe ear 10b ar- 'anged on opposite sides of the socket lita andextending )utwardly of the guiding element 16 proper to be coex- .ensivewith the holding element 18 for a preselected dis- ;ance. Theillustrated locking ears 10b are substantially 'ectangular incross-section and extend outwardly from he opposite sides of the guidingelement 10 and a transferse relationship and the ears on the same sideof a :ocket are arranged to abut the opposite sides of the ioldingelement 18. To this end, the holding socket l()84 is defined of a depthwhereby it merely hugs only )ne-half of the diameter of the holdingelement 18 in the Form of a rod, and, therefore, the ears ltlb mountedon he same side of the rod, as best seen in FIG. l. For urposes thatwill be more evident hereinafter, the side )r face of the guidingelements 10 are flat throughout its ength.

The opposite face of the guiding element 10 from the 'ace provided withthe sockets 1W is provided with a ongitudinal slot or track 16Cextending substantially he entire length thereof, as best seen byviewing the guiding element 1) on the left hand side of FIG. l. Theuiding slot or track 1d@ is defined of a depth to slidbly receive thecircuit board 16 along its correspondng edge and to securely hold it inthis position. One 1nd of each guiding element 10 is constructed to havea ransverse projection 10d having an aperture 10e there- |n arrangedrelative to the guiding slots 10c to cause he electrical connector 14and thereby the receptacle .4a to always be aligned therewith when thetwo are astened together.

The locking elements 12 are shown in the form of a plit ring. Thelocking elements 12 may also be contructed of a resilient plastic, suchas nylon, and injecion molded in various widths, The open ends of thescking element 12 are tapered to allow the locking elenent 12 proper tobe slightly expanded as it is slipped ver a holding element 1S and thelocking ears 12b for guiding element 10 piaced thereon. The resilienceof he locking element 12 is such that it firmly grips the )cking ears12b and, in tending to assume its normal hape, tightly hugs the ears andthereby snap-locks the uiding element 1@ in a rigid relationship withthe hold- 1g element 18. The width of the locking elements 12 re to beapproximately equal to twice the length of locking ear 10b.

The handle or card puller 20 may also be a molded lastic element and thetype shown in FIG. 1 is defined yith a bifurcated portion 20a with thefingers thereof naced apart to be mounted on opposite faces of thetinted circuit board 16. The card handle 20 is furier provided with anupstanding portion 2()b for gripping urposes. The handle may be securedto a corner f the printed circuit card 16 by means of a pin 21 to llowthe handle to be pivoted thereabout.

With the above structure in mind, the assembly of 1e modular componentswill now be described, The as- :mbly of two card guides l and anelectrical connector 14 can be mounted as a rigid sub-assembly or athreesided frame that can be easily moved or grouped with any number ofsimilar frames at any desired spacing. A sub-assembly may be produced bymounting the projection 10d of the guiding elements 1f! and theelectrical connector 14 adjacent an end thereof with the guide tracks10G facing inwardly thereof. These two units may then be fastenedtogether by means of a screw, such as the screw 22 shown in FIG. l,located in the aperture 10". This arrangement causes the receptacle 14ato be in alignment with the guide tracks 10G. In the same fashion, aguiding element 10 is fastened to the opposite end of the connector 14with its guide track 10 facing and in alignment with the guide track ofthe first mentioned guide element 10. This sub-assembly may then beplaced on holding elements mounted in proper relationship to receive thesockets 10 for the guide elements.

It will be assumed that the holding elements 18 are properly supportedin parallel planes, as shown in FIG. 2. For example, the top pair ofholding elements 18 are arranged in the same plane and spaced apart adistance corresponding to the width of the circuit card 16. In the samefashion, the bottom pair of holding elements 18 are supported in a planeparallel to the top pair and spaced downwardly therefrom a distancecorresponding to the length of the circuit card 16. These latter holdingelements are spaced apart from each other the same distance as the firstpair.

The locking elements 12 may then be secured to the holding elements 13by slipping them over these eienients around the locking ears 10b andallowing them to snap into position for holding the guiding elements 10in their selected position on the holding elements 18.

The locking element 12 may be arranged on opposite sides of the guidingelement 1@ to securely hold them in the selected position. It will nowbe evident that the circuit card 16 may be slipped into the connector 14by first inserting the card into the guide slots 16C adjacent the upperends of the guiding elements 10 and forced down into the guides untilthe card 16 is located into the socket 14a.

If the circuit card 16 that is stored in the above-described fashion isprovided with a handle 20, it may be simply ejected without the use of alarge amount of force or distributing the forces to the supportingstructure for the holding elements 18.- The handle 20 is grasped at thegripping portion Zib and is raised upwardly to cause the other endthereof normally overlying the adjacent portion of the guiding element10 to transmit the lifting force down through this element and therebyto the connector 14 to cause it to release the card 16 with a minimum offorce. Furthermore, when the holding elements 13 are mounted in a frame,no forces are transmitted to the frame proper.

When a plurality of circuit boards 16 are to be assembled by means ofsuch a sub-assembly or three-sided frame, they may be further arrangedto allow the circuit boards to be assembled in side-by-side fashion. Foran assembly of this type the locking elements 12 further function as aspacer between adjacent guiding elements 10. The guiding elements 10 arearranged on the holding members 18 with the locking ears llib arrangedadjacent one another whereby a locking element 12 will be slipped overthe ears 10b for both guiding elements 1G for locking both of them inposition. The spacing between the adjacent guide elements 10 can becontrolled by varying the width of the locking elements 12. The lockingelements 12 therefore are defined to abut against the adjacent Walls ofthe guilding elements 10 to space them apart in this fashion. Thissimple method of snaplocking the modular elements together may becontinued with other sub-assemblies whereby the entire holding element13 is defined as a compartment for retaining a plurality of circuitboards 16.

In addition, it should be noted that the holding elements 18 may bearranged to form compartments in a side-byside relationship. Forexample, in the arrangement of FIG. 2 an additional holding member 18may be placed to the right and/or to the left of the members showntherein. Assuming an element is arranged to the right of the holdingelements 18 of FIG. 2, the assembly for this additional iile merelyrequires that an additional subassembly be snapped to the pair ofholding members 18 shown in the drawing but arranged with the flat faceof a guide element abutting the iiat face of the locked guide element10, that is, the socket portions lila will face one another and, whenmounted on the holding members 18 of the type illustrated, will gripopposite halves of the member; as partially shown in dotted outline atthe right hand side of FIG. l. Since the locking ears 10b are alsoarranged on one side of the holding member 18, it is possible for alocking element 12 to grasp and hug the ears 10b for the two suchmounted guiding elements 10 and thereby secure them in the desiredrelationship. The adjacent filing compartment is completed by theclamping of the remaining guide element 10 to the additional holdingmember to form a unit that is suiiiciently rigid without the use of afourth holding member 18. Various other components may be arranged inthe same fashion.

Now referring to FIG. 3 wherein a drawer-type unit is shown for storingthe sub-assemblies described will be examined. The drawer-like cabinetcomprises a substantially rectangular frame 25 that may be mounted in apanel in a conventional fashion. The iile includes a ling unitcomprising holding elements 18 mounted on supporting plates 27. It willbe recognized that the holding elements 18 are the same as the elementsshown in FIGS. 1 and 2 and described hereinabove. The modular hardwareelements may therefore be assembled in this type of drawer structurewhen such a storage assembly is required. For this purpose it shouldfurther be noted that the supporting plates 27 are arranged with hingemeans at point 29 to allow the entire structure to be swingable in andout of the frame proper. The free end of the plates 27 are supported onthe pair of feet 31 arranged at the opposite end of the frame 25 tomaintain it at a level position when it is completely within the filedrawer. It will be recognized that the swingable action of the filingunit allows ready access to the electrical components that are tiled bymeans of the modular hardware.

It should now be evident that the present invention has advanced thestate of the art through the provision of modular hardware that may beSnap-locked together for forming sub-assemblies to store circuit boardsand the like and which sub-assemblies require a minimum of space forstoring large numbers of cards.

What is claimed is:

1. Hardware for mounting circuit boards and the like comprising a pairof holding elements arranged in substantially the same plane and spacedapart a distance corresponding to a preselected dimension of a circuitboard, another pair of holding elements arranged in a spaced apartrelationship in substantially the same plane and spaced from saidfirst-mentioned pair a distance corresponding to another preselecteddimension of the circuit board whereby the circuit board may beremovably mounted between said pairs of elements, a pair of circuitboard guiding elements each adapted to be mounted on and longitudinallyextend between a preselected pair of the holding elements and having alongitudinal track deiined on one side thereof to receive and secure acircuit board therein, said guiding elements being aligned in the sameplane on the holding elements and arranged with the track opening towardeach other to slidably receive the corresponding edges of a circuitboard, each of said guiding elements having socket portions adjacenttheir ends to receive and hug a holding element when clamped 6 thereto,separate means for clamping each of said guiding elements to one of theholding elements, and an electrical connector secured adjacent one endof each guiding element and aligned therewith to slidably receive andretain a circuit board inserted therein from the opposite end.

2. Hardware for mounting circuit boards and the like as defined in claim1 wherein said holding elements are mounted to a pair of supportingplates arranged at opposite ends thereof to form a circuit board filingunit, a drawer type rectangular frame for mounting and supporting thethus deiined circuit board retaining unit, and hinge means for mountingsaid filing unit to said frame and connected thereto at the ends of adifferent one of the supporting plates to allow the unit to be tiltedout of the frame to thereby allow ready access to a stored circuitboard.

3. Hardware for mounting circuit boards and the like as defined in claim1 wherein said guiding elements each include locking elements definedadjacent each of said socket portions to extend outwardly of the guideelements from opposite sides thereof, and said clamping means aresplit-ring constructed and deiined to slip over a holding element andreceive the locking elements on the opposite sides of the holdingelements to snap lock the guiding elements to their holding elements bymeans of said locking elements.

4. Hardware for mounting and tiling printed circuit cards comprising apair of holding rods arranged in substantially the same plane and spacedapart a distance corresponding to a preselected dimension of a circuitcard, another pair of holding rods spaced apart in the same plane thesame distance as said iirst-mentioned pair but in a plane parallel tosaid first-mentioned plane and spaced therefrom a distance correspondingto another preselected dimension of the circuit card, a supportingbracket mounting the opposite ends of each of said holding rods todefine a rigid unit, at least a pair of circuit card guiding elementseach adapted to be mounted between a preselected pair of holding rodsand having a longitudinal slot defined on one side thereof to slidablyreceive and secure a circuit card therein, said guiding elements beingmounted on the respective holding rods in a plane transverse to saidparallel planes and with the card receiving slots opening toward eachother to allow a circuit carc' to be slidably mounted between saidelements, each ol said guiding elements being provided with socketsadjacent the ends thereof and defined to receive and hug z holding rodwhen positioned thereon, said guiding elements each further includinglocking ears delined on op posite sides of said sockets and extendingoutwardly fron the opposite sides of the guiding elements in atransverst relationship to the face provided with the sockets to bicoextensive with the holding rod for a preselected distance at least asingle resilient locking element of a split-rinl configuration adaptedto be slightly expanded and there by slipped over a holding rod toreceive and hug the lock ing ears arranged on opposite sides of theholding rol and the same side of a guiding element to cause the guid ingelement to be snap-locked to the holding rod whe: the locking elementtends to assume its normal shap about a locking ear, an electricalconnector for each pai of aligned guiding elementshaving a receptacle toslid ably receive and secure a circuit card, and means fo securing oneend of the electrical connector to one en of a guiding element for eachaligned pair whereby th connector receptacle is arranged in the sameplane z card receiving slots to allow cards to be readily slippe intoand out of the connector receptacle and in corre electrical engagement.

5. Hardware for mounting and filing printed circu cards as defined inclaim 4 wherein a plurality of sai guiding elements are mounted on theholding rods wit the locking ears in a side-by-side relationship and th7 locking elements delined to at least snap-lock the locking ears ofadjacent guide elements to their holding rods and further functioning asspacers between the successive guiding elements. j

6. Hardware for mounting andling printed circuit cards as delined inclaim 4 wherein the guiding elements are further defined with a flatface on the side provided with the sockets and including at least anadditional holding rod mounted on the supporting bracket in one of saidparallel planes and spaced therefrom a distance corresponding to thesame preselected dimension of another circuit card to be mounted andstored by means of the additional rod and at least yanother pair ofaligned guiding elements separately mounted on the additional rod andthe adjacent pair of rods, the guiding elements mounted on said adjacentpair of rods are defined to be arranged in abutting relationship withone another with :heir corresponding flat faces and thereby socketportions facing each other and enclosing oppositesides of the ioldingrods, the same locking element for the adjacent guiding element furtherfunctioning to lock the additional guiding element, a similar lockingelement for snap-lockng the other guide element to said additionalholding rod 1nd a separate electrical connector secured to the thusnounted additional pair of guiding elements.

7. Hardware for mounting printed circuit cards as deined in claim 4wherein the circuit cards include a pivot- .ble handle mounted adjacentone corner, said handle eing defined to overlie the guiding element in asubtantially flat relationship when the circuit card is secured 1 theconnector and having an upstanding gripping porion that when gripped atsaid portion causes the force or ejecting the card from the electricalconnector to be ransmitted through the mounting hardware and therebyeadily freeing the card.

8. Modular hardware for mounting circuit boards and 1e like comprisingan elongate element having a pair f mounting sockets formed on one sidethereof adjacent s ends and adapted to receive and partially hug amountig member when clamped thereto, said element includxg lockingelements defined adjacent said sockets to eX- -fnd outwardly of theelement in a plane transverse t le plane of the element to becoextensive with a mountlg member snapped into the socket and providedwith a rcuit board track on the side opposite from said one de definedto extend longitudinaly thereof and to slid- )ly receive and secure theedge of a circuit board.

9. Hardware for mounting circuit boards and the like as :fined in claim8 wherein said one side has a iiat face 1d the sockets thereof are of adepth to allow a similar ement to be positioned to the same mountingmember ith their corresponding liat faces mounted in abutting lationshipand hugging the opposite side of the mountg member.

10. Modular hardware for mounting circuit boards and e like comprising apair of circuit board guiding eleents each having a longitudinal trackdened on one le thereof to slidably receive and secure a circuit boarderein, each of said guiding elements having socket porns adjacent theirends to receive and hug a holding :ment when clamped thereto, saidguiding elements rther including a protrusion adjacent one end arrangedthe same side thereof as said tracks and provided with aperture spacedin alignment with the track and au tctrical connector secured atopposite ends to the prolsion for each of said guiding elements by meansof e aperture thereon with the tracks of the guiding ele- :nts openingtoward each other to slidably receive and ain a circuit board insertedtherein and thereby into ctrical engagement With the connector.

11. Hardware for mounting circuit boards and the like uprising a pair ofmounting elements arranged in subntially the same plane and spaced aparta distance corponding to a preselected dimension of a circuit board,ather pair of mounting elements arranged in a spaced apart relationshipin substantially the saine plane and spaced from said #rst-mentionedpair a distance corresponding to another preselected dimension of thecircuit board, a pair of circuit board guiding elements each adapted tobe mounted on and longitudinally extend between a preselected pair ofthe mounting elements and having a longitudinal track dened on one sidethereof to receive and secure a circuit board therein, said guidingelements being aligned in the same plane on the mounting elements andarranged with the tracks facing each other to slidably receive thecorresponding edges of a circuit board, each of said guiding elementshaving socket portions adjacent their ends to receive and be secured toa mounting element, each of said guiding elements further including aprotrusio-n adjacent one end provided with an aperture spaced thereonjor aligning the tracks of each of the guiding ele-ments with anelectrical connector when secured to the protrusions, an electricalconnector for each of said pair of guiding elements, and means `forsecuring the electrical connector to said guiding elements by means ofthev aperture thereon and thereby aligning the tracks of the guidingelements with the electrical connector to allow the connector toslidably receive and retain a circuit board inserted therein from theopposite end of the guiding elements.

12. A circuit board guide element for mounting circuit boards and thelike comprising an elongate element having mounting sockets definedadjacent the ends and adapted to receive a mounting member, a circuitboard track defined on at least one side of the element to extendlongitudinally thereof for slidably receiving and securing the edge of acircuit board, said elongate element including a projecting mountingfoot adjacent one end of the elongate element provided with an aperturespaced in parallel alignment with the track for securing an electricalconnector to said guide element by means of the aperture to maintain theguide element and the secured electrical connector in the same plane,and a second similarly dened elongate element adapted to be connected tothe other end of the electrical connector to thereby maintain the twoedges of a circuit board in the the same planel when a circuit board isslidably received between the elongate elements to allow the connectorto slidably receive and retain the circuit board to thereby correctlyalign the corresponding portions of the printed circuit board and theelectrical contacts of the conductor.

13. Hardware for mounting circuit boards and the like comprising a pairof circuit board guiding elements having a longitudinalftrack defined ononey side thereof to receive and secure a circuit board therein, saidguiding elements being aligned in the same plane and spaced with thetracks facing each other to slidably receive the corresponding edges ofa circuit board, each of said guiding elements including a protrusionadjacent one end provided with an aperture spaced in parallel alignmentwithy the track and for aligning the tracks of each of the guidingelements with an electrical connector when secured to the protrusions bymeans of said apertures, an electrical connector for each of said pairsof guiding elements, means for securing the electrical connector to saidguiding elements by means of the aperture thereon and thereby aligningthe connector in the same plane with the tracks of the guiding elementsand maintaining the two edges of a circuit board and the connector inthe same plane to allow the connector to slidably receive and retain acircuit board inserted therein from the opposite end of the guidingelements to thereby correctly align the corresponding portions of theprinted circuit of the circuit board and the electrical contacts of theconnector.

14. Hardware for mounting circuit boards and the like comprising a pairof circuit board guiding elements having a longitudinal track dejned onone side thereof to receive and secure a circuit board therein, saidguiding elements being aligned in the same plane and spaced with thetracks facing each other to slidably receive the corresponding edges ofa circuit board, each of said guiding elements including a protrusionadjacent one eind provided with an aperture spaced in parallel alignmentwith the track and for aligning the tracks of each of the guidingelements with an electrical connector when secured to the protrusions bymeans of said apertures, an electrical connector for each of said pairof guiding elements, means for securing the electrical connector to saidguiding elements by means of the aperture tlzereon and thereby aligningthe connector with the tracks of the guiding elements in the same planeand maintaining the two edges of a circuit board and the connector inthe same planel to allow the connector to slidably receive and retain acircuit board inserted therein from the opposite end of the guidingelements to thereby correctly align the corresponding portions of theprinted circuit of the circuit board and the electrical contacts of theconnector, and means for mounting said guiding elements in a position toslidably receive a circuit board.

15. A circuit board guide element for mounting circuit boards and thelike comprising an elongate element having a circuit board track definedon at least one side of the element to extend longitudinally thereojcfor slidably receiving and securing the edge of a circuit board, saidelongate element including a projecting mounting foot adjacent one endof the elongate element provided with an aperture the centerline ofwhich is in parallel alignmont with the rack for securing an electricalconnector to said elongate element by means of the aperture to maintainthe elongate element and the secured electrical connector in the sameplane, and a second similarly defined elongate element adapted to beconnected to the other end of the electrical connector to therebymaintain the two edges of a circuit board in the same plane when acircuit board is slidably received between the elongate elements toallow the connector to slidably receive, and retain the circuit board tothereby correctly align the corresponding portions of the printedcircuit board and the electrical contacts of the connector.

References Cited in the le of this patent or the original patent UNITEDSTATES PATENTS 1,077,638 Petsche Nov. 4, 1913 1,345,401 Ratner July 6,1920 1,480,939 Hand Jan. 15, 1924 1,815,858 Lifschultz July 21, 19311,953,552 Dequeker Apr. 3, 1934 2,140,879 ONeal Dec. 20, 1938 2,326,029Grunt Aug. 3, 1943 2,390,309 Keys Dec. 4, 1945 2,731,609 Sobell Ian. 17,1956 2,951,185 Buck Aug. 30, 1960 2,952,810 Helton Sept. 13, 19602,976,510 Blain Mar. 21, 1961 3,008,113 Johnson Nov. 7, 1961 3,058,440Berry Oct. 16, 1962 3,061,761 Blain Oct. 30, 1962 FOREIGN PATENTS203,624 Australia Oct. 10, 1956

